2 files changed, 43 insertions, 1 deletions
diff --git a/tests/type-consistency/spec/index.ts b/tests/type-consistency/spec/index.ts
index 4532493..b2da682 100644
--- a/tests/type-consistency/spec/index.ts
+++ b/tests/type-consistency/spec/index.ts
@@ -1,5 +1,6 @@
 import array from "./array";
 import functions from "./function";
 import types from "./types";
+import tostring from "./tostring";
 
-export default [array, functions, types];
+export default [array, functions, types, tostring];
diff --git a/tests/type-consistency/spec/tostring.ts b/tests/type-consistency/spec/tostring.ts
new file mode 100644
index 0000000..4fcb803
--- /dev/null
+++ b/tests/type-consistency/spec/tostring.ts
@@ -0,0 +1,41 @@
+import path from "path";
+import { createTestHarness } from "../harness";
+
+export default createTestHarness({
+  harnessName: "ToString",
+  generatedPath: path.join(__dirname, "..", "generated"),
+})
+  .createFunctionTest({
+    name: "Passes through strings literally",
+    program: "fn(x, tostring(x))",
+    cases: [
+      { input: "hello", output: "hello" },
+      { input: "1", output: "1" },
+      { input: "[1,2,3]", output: "[1,2,3]" },
+    ],
+  })
+  .createFunctionTest({
+    name: "Is idempotent",
+    program: "fn(x, tostring(tostring(x)))",
+    cases: [
+      { input: "hello", output: "hello" },
+      { input: "1", output: "1" },
+      { input: "[1,2,3]", output: "[1,2,3]" },
+    ],
+  })
+  .createFunctionTest({
+    name: "Handles primitives",
+    program: "fn(x, tostring(x))",
+    cases: [
+      { input: 5, output: "5" },
+      { input: true, output: "true" },
+    ],
+  })
+  .createFunctionTest({
+    name: "Handles arrays and nested arrays",
+    program: "fn(x, tostring(x))",
+    cases: [
+      { input: [1, 2, 3], output: "[1, 2, 3]" },
+      { input: [1, 2, [3, 4, 5]], output: "[1, 2, [3, 4, 5]]" },
+    ],
+  });